Cleaning applications typically involve the removal of foreign matter off surfaces. In laundry applications, this involves the removal of both hydrophobic and hydrophilic soils (food stains, blood, grass, dirt, grease, oils, etc.) off various fabrics including cotton, polyester, silk, rayon, wool and various blends of these materials.
For laundry applications, the consumer has two choices for removal of soils: conventional water based cleaning and dry cleaning (i.e., non-aqueous based cleaning). Compositions suitable for use in conventional water based fabric cleaning systems have been optimized over the years. Specifically, laundry detergents that include surfactants, enzymes, builders, bleaches, chelants, polymers and other additives have been shown to remove both hydrophilic and hydrophobic soils efficiently in a water based fabric cleaning system. More specifically, while cotton, polyester and various blends can be efficiently cleaned using conventional water based systems, other more delicate fabrics, such as silk, wool, and rayon, are prone to fabric damages or shrinkages caused by the water based cleaning process and generally rely on the dry cleaning process.
The dry cleaning process refers to a process where low or no water is used in the cleaning system; it uses various non-aqueous organic solvents, such as halocarbons, hydrocarbons, densified carbon dioxide, glycol ethers and silicones. Generally, water-sensitive fabrics such as silk, wool, rayon, and the like, are cleaned in this manner.
Conventional detergent compositions and additives designed for water based cleaning. It has been found that those conventional detergent additives, including anionic surfactants (e.g. linear alkyl benzenesulfonates, alkylethoxy sulfates), bleaches and polymers (e.g., ethoxylated polyamines) are not efficient cleaning agents in dry cleaning solvents due to low compatibility with these solvents.
Some additives, such as detersive surfactants, have been developed for dry cleaning applications. An important design feature of these additives is their enhanced compatibility with the dry cleaning solvents. Not limited in theory, it is believed that these detersive surfactants can boost detergency by solubilizing the target soils; by suspending water in the dry cleaning solvents or system, if low levels of water are utilized; and by forming reverse micelles that help trapping soils for removal from the system. Surfactant detergency has been discussed in “Detergency of Specialty Surfactants”, by F. E. Friedli, Marcel Dekker, Inc., New York (1988). Use of surfactants in a dry cleaning application has been disclosed in U.S. Pat. No. 5,944,996; U.S. Pat. No. 6,548,466; U.S. Pat. No. 6,461,387; U.S. Pat. No. 6,148,644; and U.S. Pat. No. 6,114,295.
Accordingly, there is a continuing need to develop cleaning agents to enhance soil removal from various fabrics, including cotton, polycotton, polyester, silk, rayon, wool and various blends, in non-aqueous cleaning applications.
There is also a need to develop detergent additives or cleaning agents, such as detersive surfactants, that exhibit enhanced capability to solubilize laundry soils in the dry cleaning solvents. There is a further need that such detergent additives or cleaning agents have the capability to suspend water in the solvents or dry cleaning solvents or system, when water is used in the dry cleaning system.